View full sizeMarshall Space Flight Center's headquarters building 4200. Wernher von Braun worked here and so has every Marshall center director since. (File)

WASHINGTON - NASA warned its 18,000 federal employees this week that some of them will be furloughed if the federal government runs out of money Sept. 30. That warning follows White House instructions to all federal agencies this week to prepare for a spending halt.

The memo says nothing directly about the thousands of other employees employed by NASA contracts, but it does say some projects would be put on hold. And there would be no money to fund contracts without a budget.

Federal spending for 2014 is caught in a Washington power struggle between Congress and the White House over the Affordable Care Act, sequestration and other spending issues. With no budgets so far, the government's bank accounts run out Sept. 30 if nothing changes. Radzanowski's memo comes on the heels of Sept. 17 White House instructions to all federal agencies to prepare for a spending halt.

"The Administration strongly believes that a lapse in funding should not occur," Radzanowski says in the memo. "There is enough time for Congress to prevent a lapse in appropriations, and the Administration is willing to work with Congress to enact a short-term continuing resolution to fund critical government operations and allow Congress the time to complete the full year 2014 appropriations."

So, is the government, including NASA, being prudent or alarmist? Or is this simply a heads-up to NASA workers that the situation is real and, as one government workers' union warned its members, it's a good idea to set aside some money just in case the wheels do come off in Washington this month?